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Nicholas Kamm / AFP / Getty Images
People stand in a square outside the courthouse after an earthquake was felt in New York Tuesday, causing buildings to be evacuated. The Pentagon, the U.S. Capitol and Union Station in the nation's capital were all evacuated after the 5.9-magnitude quake, which was shallow with its epicenter only 0.6 miles (one kilometer) underground.
A magnitude-5.8 earthquake in Virginia Tuesday afternoon was felt across the U.S. East Coast, shaking offices and nerves from Washington D.C. to New York City and as far south as Chapel Hill, North Carolina. There are even reports of shaking as far west as Columbus, Ohio, and out on Martha's Vineyard.
That's a whole lot of shaking for what amounts to a medium-sized quake. The reason for its reach, according to the U.S. Geological Survey, is geology of the East Coast.
"The reason an earthquake in the high 5s is felt so far away is that it occurred in an area … where the bedrock is solid, it's not really fractured or broken up by faults the way it would be, say, in California," Peter Powers, a geophysicist with the survey, told me today.
The seismic energy in areas with stable bedrock — "stable continental craton" in geophysics speak — can travel much farther than it can when broken up by young faults.
"Seismic energy attenuates very slowly on the East Coast," Powers said. "On the West Coast it attenuates much more rapidly because the bedrock is fractured and faulted and much more variable in its composition than on the East Coast."
Seismologist Dr. Lucy Jones joins Brian Williams from the United States Geological Survey headquarters in Pasadena, Calif.
The survey notes that earthquakes in the central and eastern U.S. are typically felt over a much broader region than those in the Western U.S., sometimes an area as much as ten time larger than similar magnitude earthquake on the West Coast.
"A magnitude 5.5 eastern U.S. earthquake usually can be felt as far as 300 miles from where it occurred, and sometimes causes damage as far away as 25 miles," the agency notes on its website.
Early reports indicated the depth of the earthquake is also quite shallow — just 3.7 miles down in the Earth's crust. Powers said this would likely be revised deeper as time goes by and the data is further analyzed, but depth here isn't much of a factor in the shaking.
The earthquake today on the East Coast, Powers said, was large enough to be felt over a large area no matter if its depth is ultimately determined to be 3 miles or 15 miles deep. "At that point, the depth really isn't much of a factor."
Depth can be a factor
In other regions, however, depth of an earthquake can make a difference.
Generally, the closer the epicenter of an earthquake is to the surface, the stronger the shaking on the surface and the more damage they cause, no matter what their size.
Conversely, when earthquakes rupture deeper in the crust — they can rupture up to 500 miles deep — more energy is lost as it races to the surface.
That's one reason why some relatively strong earthquakes, originating deep in the crust, cause little damage on the surface whereas some seemingly small earthquakes can cause massive damage.
The 7.0 magnitude earthquake in Haiti in January 2010 was 8.1 miles deep. The relatively shallow depth combined with subpar construction in Haiti caused massive damage there.
A pair of minor earthquakes in Spain this May ruptured just over half a mile below the ground, causing several deaths and damaging buildings in a part of the world with a tame seismic history.
The 9.0 magnitude earthquake hit Japan on March 11 began at a depth of 19.9 miles. Though devastating, it could have been worse had it been even shallower — and had Japan's infrastructure not been among some of the most earthquake ready in the world.
John Roach is a contributing writer for msnbc.com. Connect with the Cosmic Log community by hitting the "like" button on the Cosmic Log Facebook page or following msnbc.com's science editor, Alan Boyle, on Twitter (@b0yle).
NBC's Tom Costello reports from the earthquake epicenter in Mineral, Va., where the roof of the town hall collapsed in the quake.
An 5.8-magnitude earthquake in central Virginia was felt across much of the East Coast on Tuesday, causing light damage and forcing thousands of people to evacuate buildings in New York, Washington and other cities. NBC's Lester Holt reports.
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sssssuuuuurrrreeee!!!!!!
So apparently is was felt as far north as Montreal. Furthest south I've seen is Charleston SC. As far west as Detroit. (one person on here said they felt it in Iowa).
RNroulston:
Eleven thousand years ago the Ice scoured half the state of Wisconsin, Minnesota and Upper Michigan, we have a large granite and basalt base which will take up the shock. No faults here.
Don't move here to save yourselves in 2012 if you are a Democrat, we have enough already. But then when the going gets tough, they mostly run away to Illinois, so move there first and save yourselves some moving expenses.
Felt it here in Blacksburg. Thought it was just an extra big hit by a Hokie lineman during practice.
Nothing down here in Florida, AND, we skated Hurricane Irene. We do have Casey Anthony coming back, trade anyone?
ABOLISH EARTHQUAKES!
Vote for Ron Paul in 2012!!!
www.RONPAUL2012.com
How soon until the Religious Right blames gays for this?
2012 is a joke The Mayan Calender runs out.. So what! these primitve indians Predict the end of the Earth? it runs out you start a new Calender.. no big deal!
I'm in MA and didn't feel it but a few friends as far north as ME felt it.
I heard it was the mother "frackers" who caused it! What the frack!
Its funny to hear others recount their exprience on such a minor earthquake. We're so immune to it here on the west coast. Sometimes you sleep through an earthquake over here. Either way, hope you all enjoyed the quake as much as we enjoy our earthquakes over here. :)
Hey! You guys freaked out like when Portland, OR got a blizzard two years ago.
In any case, why is it the end of the world when it's a 5.9? I've been rocking those ever since the 9.0 came on March 11th. Those are aftershocks for me. Go back to work.
From a resident in Japan.
earth is just making LOVE ...woke up with a (wink)and a smile
2012 hmmm we may just be out of virgin...oh well back to sheep :)
Even the bible says the world will not end at the "end". It continues further for at least 1000 years of peace. Peaceful because Jesus is there with an iron rod whacking people. Don't believe me then read the bible again. It might not specifically mention the whacking part but the iron rod and 1000 years of peace after the end of the world is all there. And what happens after 1000 years? Apparently they "must" allow evil to stir things up again. I think a more likely story is the actual landlords of this place return then and clear the current dog and pony show out. But regardless this world "ends" every several thousand years.
life is forever there is no end but end itself ... i see the bible as a ol news paper that dad forgot to throw away
once you buy into a MOB story ..you will follow it like a river
and you will take whatever is in your way
You are correct in only one aspect, the world will end but it will take around 4.5 billion years till the eartsh demise. Of course us humans (if we stay on this blue sphere) will have long ago turned to dust. Can you say red giant? We have about 3+ billion years I would hope in that time we have spread out into the universe, if not then we deserve to be charbroiled by our Sun.
I was in Georgia Western Side of the state. Getting ready for bow season on a small foot hill of the Appalachian mountains. Setting up my treestand. Did not feel a thing there today?
We felt it in Augusta GA - significant tremors in our 3-floor LARGE brick office building ... there was no mistaking that it was an earthquake .... was even stronger at my home.
"Columbus, Ohio"?
Try Louisville, Kentucky. My office is on the 8th floor of the building and all of us felt the building swaying. We congregated in the hall and talked about it, but it did not appear to be frightening. In any event, Louisville, KY is one heck of a long way from Mineral, VA.
Sorry, Osama is killing NASA (where is your space shuttle?) so there is no rocket anymore. Perhaps we could bum a ride from the Russians, or Chineese, or India, or the EU. I hear the Ausies may be getting something together too.
The shallow earthquake appears to be centered in and around the top secret US Government deep underground complexes beneath Mt. Weather and fanning out across Virgina.
Was this earthquake a US Military test to evacuate a large cavern to expand the already enormous underground caverns, lakes, roads, cities, underground malls?
One thing this earthquake exposed was the utter FOLLY of the US Gov. spending a Trillion dollars of taxpayer dollars placing a replacement US Gov. deep beneath Virginia where 100 Russian MIRV'd warheads would easily shatter them thru the massive ground displacement bouncing against the Eastern teutonic plate.
You'd think the US Geological agency's would have figured that out BEFORE sinking 1 Trillion US taxpayer dollars into such an enormous hidden series of deep underground complexes, such a mistake you'd expect from a 3rd. world nation!
Oh wait, America is rapidly becoming a 3rd. world nation, a banana republic where the entire REPLACEMENT US GOVERNMENT consists of unelected Americans all living underground rolling fat off the American taxpayers paying for their luxury deep underground cities and digs.
Virgina's Mount Weather Secret Underground Complex home of US Gov.Shadow Government of Cabinet,Presidental replacements http://is.gd/De0FGi
Hmmmm........isn't this quake about as deep as the Marcellus Shale Fracturing that is occurring in this area?!?
Wonder what is to come of all the Marcellus drilling operations into the solid - now heavily fractured 'stable' bedrock?!?
Civil authorities here in the East made a bad call in ordering buildings to be evacuated in urban areas. The streets were jammed with people milling about the streets beneath skyscrapers which would have rained debris on them had there been a strong aftershock.
Grand Rapids, Michigan --- our office building swayed here! Even though the quake made local news in Michigan, none of the reports indicate that anyone knows it reached this far. We literally 'swayed' in West Michigan.
The only fear man has is Man himself. Man has killed more humans then mother nature by far. I wouldn't worry about 2012 i would worry about some crack pot losing his or hers mind and ending you.
I lived in Charlottesville and Scottsville VA for over 10yrs. There were multiple earthquakes while I lived there. Most were centered out of Columbia, VA which is south of Mineral, VA. I think all this hoopla is just more media grandstanding making a big event out of something relatively normal. I understand this is the biggest in many years, but even so, all that's being reported is more sensationalistic and scaring people. The whole tone could be diffferent IMO.
Word of advice to all you east coasters, unless you want to get bashed in the head by falling debris, do not run outside during or right after and earthquake. Duck and cover and be prepared to take care of the panicking deer that head toward the doors in a flight of panicky fear. Losing your head in a disaster is a sure way to get oneself killed so NO NOT PANIC think before you act it could save your life.